In-vivo measuring systems and other types of in-vivo systems (e.g., in-vivo devices for performing surgical and the like operations) are known in the art. Some in-vivo devices/systems, which may traverse the gastrointestinal (“GI”) system (mouth-to-anus), or other body organs/systems, may include an imaging sensor, or imager, for imaging (e.g., taking pictures of) the interior of the GI system. An in-vivo device may include one or more imagers and/or other sensors (e.g., pressure sensor, pH sensor, etc.). Other in-vivo devices may alternatively or additionally include a medication container and means for administering medication in the GI system. Other in-vivo devices may include means for performing surgical operations in vivo, and so on. Autonomous in-vivo devices are devices that traverse the GI system by being pushed in the GI system by peristaltic force exerted by the digestive system. Autonomous in-vivo devices may also spasmodically move in the intestinal tract in ‘fits and starts’.
A swallowed in-vivo device may communicate with an external receiver. (When used herein “external” means in the subject but external to the swallowed in-vivo device, or external to the subject in which the swallowed device is located.) The external receiver may be worn by a subject in order to transfer images (and/or other sensory information) from the in-vivo device to the receiver, and, optionally, to transfer commands from the receiver to the in-vivo device, for example to change a mode of operation (e.g., a rate at which image frames are to be transmitted to the external receiver).
There are instances in which the communication between an in-vivo device and the external receiver is performed by using radio frequency (“RF”) signals, and there are other instances in which the communication is performed by using non-RF techniques. Capsule type endoscopes made by Given Imaging, Israel, use RF communication means. Capsule type endoscopes made by Korea Institution of Science and Technology (“KIST”), Korea, includes a set of electrodes to communicate with an external receiver through contact (of the electrodes) with the subject's body.
RF communication between an in-vivo device and an external receiver is stated by KIST to have drawbacks. For example, according to KIST, since RF signals are used to transmit data, power consumption is large, thereby shortening operation time of the device, and reception sensitivity is worsened by, or deteriorated due to, electromagnetic interferences caused by various electronic appliances. In addition, KIST asserts that the circuit converting a video signal into a high frequency signal, and the antenna used for signal transmission, etc., increase the in-vivo device's real estate and production cost. KIST also asserts that using a high radio frequency may harm the human body.
Passing an electrical current through the body, as KIST does with its electrodes, may also pose some risks with respect to the human body though using that technique may enable faster data transfer (comparing to RF communication) to the external receiver. In the electrodes-based communication technique proposed by KIST the electrodes have to contact the body during communication in order to maintain communication continuity (e.g., avoid communication gaps). However, due to the capsule propagation nature (usually through peristalsis of the GI system) and environment in which the in-vivo device moves (the gastrointestinal system), communication gaps are likely to occur. Nevertheless, KIST does not seem to address the problem of communication gaps resulting from bad or unstable electrodes-body, contact or from complete loss of electrodes-body contact.